hstein3:Priapetic: You know, I understand that e. coli is so well studied we know more about it and its genome than just about anything else, but do we really need to do all of our genetic experimentation on a species of bacteria that is highly capable of colonizing our bodies?

IIRC, most E. coli used for lab work is rendered incapable of infecting humans. Even still, laboratory conditions are kept to ensure that it doesn't escape into the wild, so to speak. It's not like scientists are brewing this stuff up then spreading it on their sandwiches.

Yeah, most E. coli strains commonly used in the laboratory are non-pathogenic domesticated lab strains. They long ago lost the ability to colonize the human gut. If by some chance they got in their, they would be quickly out competed by your natural flora.

The author made a small typo / grammatical mistake (using just "it" instead of "its"). Subby just completely bungled the meaning of the sentence.

From TFA: so Barrick's team set out to transfer it (sic) genetic ability to metabolize caffeine into E. coli

They set out to transfer the "genetic ability" into E. coli, which is to say the genes for enzymes for caffeine metabolism. They are not saying they've developed a bacteria that can make E. coli out of caffeine. Once they've isolated the genes they want to transfer, this is not a difficult task.